This application claims the priority of German patent document 198 19 709.8, filed May 2, 1998, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a range warning radar dome made of a radar transparent material which has a metallically glossy layer, and to a method of manufacturing such a radar dome.
According to the current state of the art, radar radomes are designed with the thickness of the radome and the dielectric material constant is coordinated with the wavelength of the frequency which is used. In this manner, reflection losses at boundary surfaces, the absorption losses at boundary surfaces and absorption losses in the radome material can be minimized.
A design which includes a maker's emblem in a raised form within a visually partially transparent radome structure in a Range Warning Radar (RWR) system, has not been known so far.
Also new is the provision of a scratch-resistant surface made of SiO.sub.2 on or in combination with a radome. Such a scratch-resistant SiO.sub.2 -layer can be applied by a sol-gel technique or by Chemical Vapor Deposition (CVD=depositing layers of material on a substrate from the gaseous phase).
It is an object of the present invention to provide a process and apparatus such as described above, by means of which characteristic structures having a specific appearance can be provided; with simultaneous full radar transparency, without influencing the propagation of the radar waves, and maintaining the imaging characteristics of the radome.
This and other objects and advantages are achieved by the method and apparatus according to the invention, in which a cover plate of the radar dome is both radar transparent and visually transparent. An emblem or other symbol is molded into the cover plate in negative relief and is provided with a metallically glossy layer, whose thickness is such that visible electromagnetic waves are reflected, and longer wave (radar) electromagnetic radiation is transmitted with substantially no attenuation.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.